diff options
Diffstat (limited to 'drivers/thunderbolt/usb4.c')
| -rw-r--r-- | drivers/thunderbolt/usb4.c | 764 |
1 files changed, 764 insertions, 0 deletions
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c new file mode 100644 index 000000000000..b341fc60c4ba --- /dev/null +++ b/drivers/thunderbolt/usb4.c @@ -0,0 +1,764 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * USB4 specific functionality + * + * Copyright (C) 2019, Intel Corporation + * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> + * Rajmohan Mani <rajmohan.mani@intel.com> + */ + +#include <linux/delay.h> +#include <linux/ktime.h> + +#include "tb.h" + +#define USB4_DATA_DWORDS 16 +#define USB4_DATA_RETRIES 3 + +enum usb4_switch_op { + USB4_SWITCH_OP_QUERY_DP_RESOURCE = 0x10, + USB4_SWITCH_OP_ALLOC_DP_RESOURCE = 0x11, + USB4_SWITCH_OP_DEALLOC_DP_RESOURCE = 0x12, + USB4_SWITCH_OP_NVM_WRITE = 0x20, + USB4_SWITCH_OP_NVM_AUTH = 0x21, + USB4_SWITCH_OP_NVM_READ = 0x22, + USB4_SWITCH_OP_NVM_SET_OFFSET = 0x23, + USB4_SWITCH_OP_DROM_READ = 0x24, + USB4_SWITCH_OP_NVM_SECTOR_SIZE = 0x25, +}; + +#define USB4_NVM_READ_OFFSET_MASK GENMASK(23, 2) +#define USB4_NVM_READ_OFFSET_SHIFT 2 +#define USB4_NVM_READ_LENGTH_MASK GENMASK(27, 24) +#define USB4_NVM_READ_LENGTH_SHIFT 24 + +#define USB4_NVM_SET_OFFSET_MASK USB4_NVM_READ_OFFSET_MASK +#define USB4_NVM_SET_OFFSET_SHIFT USB4_NVM_READ_OFFSET_SHIFT + +#define USB4_DROM_ADDRESS_MASK GENMASK(14, 2) +#define USB4_DROM_ADDRESS_SHIFT 2 +#define USB4_DROM_SIZE_MASK GENMASK(19, 15) +#define USB4_DROM_SIZE_SHIFT 15 + +#define USB4_NVM_SECTOR_SIZE_MASK GENMASK(23, 0) + +typedef int (*read_block_fn)(struct tb_switch *, unsigned int, void *, size_t); +typedef int (*write_block_fn)(struct tb_switch *, const void *, size_t); + +static int usb4_switch_wait_for_bit(struct tb_switch *sw, u32 offset, u32 bit, + u32 value, int timeout_msec) +{ + ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec); + + do { + u32 val; + int ret; + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, offset, 1); + if (ret) + return ret; + + if ((val & bit) == value) + return 0; + + usleep_range(50, 100); + } while (ktime_before(ktime_get(), timeout)); + + return -ETIMEDOUT; +} + +static int usb4_switch_op_read_data(struct tb_switch *sw, void *data, + size_t dwords) +{ + if (dwords > USB4_DATA_DWORDS) + return -EINVAL; + + return tb_sw_read(sw, data, TB_CFG_SWITCH, ROUTER_CS_9, dwords); +} + +static int usb4_switch_op_write_data(struct tb_switch *sw, const void *data, + size_t dwords) +{ + if (dwords > USB4_DATA_DWORDS) + return -EINVAL; + + return tb_sw_write(sw, data, TB_CFG_SWITCH, ROUTER_CS_9, dwords); +} + +static int usb4_switch_op_read_metadata(struct tb_switch *sw, u32 *metadata) +{ + return tb_sw_read(sw, metadata, TB_CFG_SWITCH, ROUTER_CS_25, 1); +} + +static int usb4_switch_op_write_metadata(struct tb_switch *sw, u32 metadata) +{ + return tb_sw_write(sw, &metadata, TB_CFG_SWITCH, ROUTER_CS_25, 1); +} + +static int usb4_switch_do_read_data(struct tb_switch *sw, u16 address, + void *buf, size_t size, read_block_fn read_block) +{ + unsigned int retries = USB4_DATA_RETRIES; + unsigned int offset; + + offset = address & 3; + address = address & ~3; + + do { + size_t nbytes = min_t(size_t, size, USB4_DATA_DWORDS * 4); + unsigned int dwaddress, dwords; + u8 data[USB4_DATA_DWORDS * 4]; + int ret; + + dwaddress = address / 4; + dwords = ALIGN(nbytes, 4) / 4; + + ret = read_block(sw, dwaddress, data, dwords); + if (ret) { + if (ret == -ETIMEDOUT) { + if (retries--) + continue; + ret = -EIO; + } + return ret; + } + + memcpy(buf, data + offset, nbytes); + + size -= nbytes; + address += nbytes; + buf += nbytes; + } while (size > 0); + + return 0; +} + +static int usb4_switch_do_write_data(struct tb_switch *sw, u16 address, + const void *buf, size_t size, write_block_fn write_next_block) +{ + unsigned int retries = USB4_DATA_RETRIES; + unsigned int offset; + + offset = address & 3; + address = address & ~3; + + do { + u32 nbytes = min_t(u32, size, USB4_DATA_DWORDS * 4); + u8 data[USB4_DATA_DWORDS * 4]; + int ret; + + memcpy(data + offset, buf, nbytes); + + ret = write_next_block(sw, data, nbytes / 4); + if (ret) { + if (ret == -ETIMEDOUT) { + if (retries--) + continue; + ret = -EIO; + } + return ret; + } + + size -= nbytes; + address += nbytes; + buf += nbytes; + } while (size > 0); + + return 0; +} + +static int usb4_switch_op(struct tb_switch *sw, u16 opcode, u8 *status) +{ + u32 val; + int ret; + + val = opcode | ROUTER_CS_26_OV; + ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1); + if (ret) + return ret; + + ret = usb4_switch_wait_for_bit(sw, ROUTER_CS_26, ROUTER_CS_26_OV, 0, 500); + if (ret) + return ret; + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1); + if (val & ROUTER_CS_26_ONS) + return -EOPNOTSUPP; + + *status = (val & ROUTER_CS_26_STATUS_MASK) >> ROUTER_CS_26_STATUS_SHIFT; + return 0; +} + +/** + * usb4_switch_setup() - Additional setup for USB4 device + * @sw: USB4 router to setup + * + * USB4 routers need additional settings in order to enable all the + * tunneling. This function enables USB and PCIe tunneling if it can be + * enabled (e.g the parent switch also supports them). If USB tunneling + * is not available for some reason (like that there is Thunderbolt 3 + * switch upstream) then the internal xHCI controller is enabled + * instead. + */ +int usb4_switch_setup(struct tb_switch *sw) +{ + struct tb_switch *parent; + bool tbt3, xhci; + u32 val = 0; + int ret; + + if (!tb_route(sw)) + return 0; + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_6, 1); + if (ret) + return ret; + + xhci = val & ROUTER_CS_6_HCI; + tbt3 = !(val & ROUTER_CS_6_TNS); + + tb_sw_dbg(sw, "TBT3 support: %s, xHCI: %s\n", + tbt3 ? "yes" : "no", xhci ? "yes" : "no"); + + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1); + if (ret) + return ret; + + parent = tb_switch_parent(sw); + + if (tb_switch_find_port(parent, TB_TYPE_USB3_DOWN)) { + val |= ROUTER_CS_5_UTO; + xhci = false; + } + + /* Only enable PCIe tunneling if the parent router supports it */ + if (tb_switch_find_port(parent, TB_TYPE_PCIE_DOWN)) { + val |= ROUTER_CS_5_PTO; + /* + * xHCI can be enabled if PCIe tunneling is supported + * and the parent does not have any USB3 dowstream + * adapters (so we cannot do USB 3.x tunneling). + */ + if (xhci) + val |= ROUTER_CS_5_HCO; + } + + /* TBT3 supported by the CM */ + val |= ROUTER_CS_5_C3S; + /* Tunneling configuration is ready now */ + val |= ROUTER_CS_5_CV; + + ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1); + if (ret) + return ret; + + return usb4_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_CR, + ROUTER_CS_6_CR, 50); +} + +/** + * usb4_switch_read_uid() - Read UID from USB4 router + * @sw: USB4 router + * + * Reads 64-bit UID from USB4 router config space. + */ +int usb4_switch_read_uid(struct tb_switch *sw, u64 *uid) +{ + return tb_sw_read(sw, uid, TB_CFG_SWITCH, ROUTER_CS_7, 2); +} + +static int usb4_switch_drom_read_block(struct tb_switch *sw, + unsigned int dwaddress, void *buf, + size_t dwords) +{ + u8 status = 0; + u32 metadata; + int ret; + + metadata = (dwords << USB4_DROM_SIZE_SHIFT) & USB4_DROM_SIZE_MASK; + metadata |= (dwaddress << USB4_DROM_ADDRESS_SHIFT) & + USB4_DROM_ADDRESS_MASK; + + ret = usb4_switch_op_write_metadata(sw, metadata); + if (ret) + return ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_DROM_READ, &status); + if (ret) + return ret; + + if (status) + return -EIO; + + return usb4_switch_op_read_data(sw, buf, dwords); +} + +/** + * usb4_switch_drom_read() - Read arbitrary bytes from USB4 router DROM + * @sw: USB4 router + * + * Uses USB4 router operations to read router DROM. For devices this + * should always work but for hosts it may return %-EOPNOTSUPP in which + * case the host router does not have DROM. + */ +int usb4_switch_drom_read(struct tb_switch *sw, unsigned int address, void *buf, + size_t size) +{ + return usb4_switch_do_read_data(sw, address, buf, size, + usb4_switch_drom_read_block); +} + +static int usb4_set_port_configured(struct tb_port *port, bool configured) +{ + int ret; + u32 val; + + ret = tb_port_read(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); + if (ret) + return ret; + + if (configured) + val |= PORT_CS_19_PC; + else + val &= ~PORT_CS_19_PC; + + return tb_port_write(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); +} + +/** + * usb4_switch_configure_link() - Set upstream USB4 link configured + * @sw: USB4 router + * + * Sets the upstream USB4 link to be configured for power management + * purposes. + */ +int usb4_switch_configure_link(struct tb_switch *sw) +{ + struct tb_port *up; + + if (!tb_route(sw)) + return 0; + + up = tb_upstream_port(sw); + return usb4_set_port_configured(up, true); +} + +/** + * usb4_switch_unconfigure_link() - Un-set upstream USB4 link configuration + * @sw: USB4 router + * + * Reverse of usb4_switch_configure_link(). + */ +void usb4_switch_unconfigure_link(struct tb_switch *sw) +{ + struct tb_port *up; + + if (sw->is_unplugged || !tb_route(sw)) + return; + + up = tb_upstream_port(sw); + usb4_set_port_configured(up, false); +} + +/** + * usb4_switch_lane_bonding_possible() - Are conditions met for lane bonding + * @sw: USB4 router + * + * Checks whether conditions are met so that lane bonding can be + * established with the upstream router. Call only for device routers. + */ +bool usb4_switch_lane_bonding_possible(struct tb_switch *sw) +{ + struct tb_port *up; + int ret; + u32 val; + + up = tb_upstream_port(sw); + ret = tb_port_read(up, &val, TB_CFG_PORT, up->cap_usb4 + PORT_CS_18, 1); + if (ret) + return false; + + return !!(val & PORT_CS_18_BE); +} + +/** + * usb4_switch_set_sleep() - Prepare the router to enter sleep + * @sw: USB4 router + * + * Enables wakes and sets sleep bit for the router. Returns when the + * router sleep ready bit has been asserted. + */ +int usb4_switch_set_sleep(struct tb_switch *sw) +{ + int ret; + u32 val; + + /* Set sleep bit and wait for sleep ready to be asserted */ + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1); + if (ret) + return ret; + + val |= ROUTER_CS_5_SLP; + + ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1); + if (ret) + return ret; + + return usb4_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_SLPR, + ROUTER_CS_6_SLPR, 500); +} + +/** + * usb4_switch_nvm_sector_size() - Return router NVM sector size + * @sw: USB4 router + * + * If the router supports NVM operations this function returns the NVM + * sector size in bytes. If NVM operations are not supported returns + * %-EOPNOTSUPP. + */ +int usb4_switch_nvm_sector_size(struct tb_switch *sw) +{ + u32 metadata; + u8 status; + int ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_SECTOR_SIZE, &status); + if (ret) + return ret; + + if (status) + return status == 0x2 ? -EOPNOTSUPP : -EIO; + + ret = usb4_switch_op_read_metadata(sw, &metadata); + if (ret) + return ret; + + return metadata & USB4_NVM_SECTOR_SIZE_MASK; +} + +static int usb4_switch_nvm_read_block(struct tb_switch *sw, + unsigned int dwaddress, void *buf, size_t dwords) +{ + u8 status = 0; + u32 metadata; + int ret; + + metadata = (dwords << USB4_NVM_READ_LENGTH_SHIFT) & + USB4_NVM_READ_LENGTH_MASK; + metadata |= (dwaddress << USB4_NVM_READ_OFFSET_SHIFT) & + USB4_NVM_READ_OFFSET_MASK; + + ret = usb4_switch_op_write_metadata(sw, metadata); + if (ret) + return ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_READ, &status); + if (ret) + return ret; + + if (status) + return -EIO; + + return usb4_switch_op_read_data(sw, buf, dwords); +} + +/** + * usb4_switch_nvm_read() - Read arbitrary bytes from router NVM + * @sw: USB4 router + * @address: Starting address in bytes + * @buf: Read data is placed here + * @size: How many bytes to read + * + * Reads NVM contents of the router. If NVM is not supported returns + * %-EOPNOTSUPP. + */ +int usb4_switch_nvm_read(struct tb_switch *sw, unsigned int address, void *buf, + size_t size) +{ + return usb4_switch_do_read_data(sw, address, buf, size, + usb4_switch_nvm_read_block); +} + +static int usb4_switch_nvm_set_offset(struct tb_switch *sw, + unsigned int address) +{ + u32 metadata, dwaddress; + u8 status = 0; + int ret; + + dwaddress = address / 4; + metadata = (dwaddress << USB4_NVM_SET_OFFSET_SHIFT) & + USB4_NVM_SET_OFFSET_MASK; + + ret = usb4_switch_op_write_metadata(sw, metadata); + if (ret) + return ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_SET_OFFSET, &status); + if (ret) + return ret; + + return status ? -EIO : 0; +} + +static int usb4_switch_nvm_write_next_block(struct tb_switch *sw, + const void *buf, size_t dwords) +{ + u8 status; + int ret; + + ret = usb4_switch_op_write_data(sw, buf, dwords); + if (ret) + return ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_WRITE, &status); + if (ret) + return ret; + + return status ? -EIO : 0; +} + +/** + * usb4_switch_nvm_write() - Write to the router NVM + * @sw: USB4 router + * @address: Start address where to write in bytes + * @buf: Pointer to the data to write + * @size: Size of @buf in bytes + * + * Writes @buf to the router NVM using USB4 router operations. If NVM + * write is not supported returns %-EOPNOTSUPP. + */ +int usb4_switch_nvm_write(struct tb_switch *sw, unsigned int address, + const void *buf, size_t size) +{ + int ret; + + ret = usb4_switch_nvm_set_offset(sw, address); + if (ret) + return ret; + + return usb4_switch_do_write_data(sw, address, buf, size, + usb4_switch_nvm_write_next_block); +} + +/** + * usb4_switch_nvm_authenticate() - Authenticate new NVM + * @sw: USB4 router + * + * After the new NVM has been written via usb4_switch_nvm_write(), this + * function triggers NVM authentication process. If the authentication + * is successful the router is power cycled and the new NVM starts + * running. In case of failure returns negative errno. + */ +int usb4_switch_nvm_authenticate(struct tb_switch *sw) +{ + u8 status = 0; + int ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_AUTH, &status); + if (ret) + return ret; + + switch (status) { + case 0x0: + tb_sw_dbg(sw, "NVM authentication successful\n"); + return 0; + case 0x1: + return -EINVAL; + case 0x2: + return -EAGAIN; + case 0x3: + return -EOPNOTSUPP; + default: + return -EIO; + } +} + +/** + * usb4_switch_query_dp_resource() - Query availability of DP IN resource + * @sw: USB4 router + * @in: DP IN adapter + * + * For DP tunneling this function can be used to query availability of + * DP IN resource. Returns true if the resource is available for DP + * tunneling, false otherwise. + */ +bool usb4_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in) +{ + u8 status; + int ret; + + ret = usb4_switch_op_write_metadata(sw, in->port); + if (ret) + return false; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_QUERY_DP_RESOURCE, &status); + /* + * If DP resource allocation is not supported assume it is + * always available. + */ + if (ret == -EOPNOTSUPP) + return true; + else if (ret) + return false; + + return !status; +} + +/** + * usb4_switch_alloc_dp_resource() - Allocate DP IN resource + * @sw: USB4 router + * @in: DP IN adapter + * + * Allocates DP IN resource for DP tunneling using USB4 router + * operations. If the resource was allocated returns %0. Otherwise + * returns negative errno, in particular %-EBUSY if the resource is + * already allocated. + */ +int usb4_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in) +{ + u8 status; + int ret; + + ret = usb4_switch_op_write_metadata(sw, in->port); + if (ret) + return ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_ALLOC_DP_RESOURCE, &status); + if (ret == -EOPNOTSUPP) + return 0; + else if (ret) + return ret; + + return status ? -EBUSY : 0; +} + +/** + * usb4_switch_dealloc_dp_resource() - Releases allocated DP IN resource + * @sw: USB4 router + * @in: DP IN adapter + * + * Releases the previously allocated DP IN resource. + */ +int usb4_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in) +{ + u8 status; + int ret; + + ret = usb4_switch_op_write_metadata(sw, in->port); + if (ret) + return ret; + + ret = usb4_switch_op(sw, USB4_SWITCH_OP_DEALLOC_DP_RESOURCE, &status); + if (ret == -EOPNOTSUPP) + return 0; + else if (ret) + return ret; + + return status ? -EIO : 0; +} + +static int usb4_port_idx(const struct tb_switch *sw, const struct tb_port *port) +{ + struct tb_port *p; + int usb4_idx = 0; + + /* Assume port is primary */ + tb_switch_for_each_port(sw, p) { + if (!tb_port_is_null(p)) + continue; + if (tb_is_upstream_port(p)) + continue; + if (!p->link_nr) { + if (p == port) + break; + usb4_idx++; + } + } + + return usb4_idx; +} + +/** + * usb4_switch_map_pcie_down() - Map USB4 port to a PCIe downstream adapter + * @sw: USB4 router + * @port: USB4 port + * + * USB4 routers have direct mapping between USB4 ports and PCIe + * downstream adapters where the PCIe topology is extended. This + * function returns the corresponding downstream PCIe adapter or %NULL + * if no such mapping was possible. + */ +struct tb_port *usb4_switch_map_pcie_down(struct tb_switch *sw, + const struct tb_port *port) +{ + int usb4_idx = usb4_port_idx(sw, port); + struct tb_port *p; + int pcie_idx = 0; + + /* Find PCIe down port matching usb4_port */ + tb_switch_for_each_port(sw, p) { + if (!tb_port_is_pcie_down(p)) + continue; + + if (pcie_idx == usb4_idx && !tb_pci_port_is_enabled(p)) + return p; + + pcie_idx++; + } + + return NULL; +} + +/** + * usb4_switch_map_usb3_down() - Map USB4 port to a USB3 downstream adapter + * @sw: USB4 router + * @port: USB4 port + * + * USB4 routers have direct mapping between USB4 ports and USB 3.x + * downstream adapters where the USB 3.x topology is extended. This + * function returns the corresponding downstream USB 3.x adapter or + * %NULL if no such mapping was possible. + */ +struct tb_port *usb4_switch_map_usb3_down(struct tb_switch *sw, + const struct tb_port *port) +{ + int usb4_idx = usb4_port_idx(sw, port); + struct tb_port *p; + int usb_idx = 0; + + /* Find USB3 down port matching usb4_port */ + tb_switch_for_each_port(sw, p) { + if (!tb_port_is_usb3_down(p)) + continue; + + if (usb_idx == usb4_idx && !tb_usb3_port_is_enabled(p)) + return p; + + usb_idx++; + } + + return NULL; +} + +/** + * usb4_port_unlock() - Unlock USB4 downstream port + * @port: USB4 port to unlock + * + * Unlocks USB4 downstream port so that the connection manager can + * access the router below this port. + */ +int usb4_port_unlock(struct tb_port *port) +{ + int ret; + u32 val; + + ret = tb_port_read(port, &val, TB_CFG_PORT, ADP_CS_4, 1); + if (ret) + return ret; + + val &= ~ADP_CS_4_LCK; + return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_4, 1); +} |